Pattern forming method and manufacturing method of magnetic recording medium

Patent metadata

Field	Value
Publication number	US-9412405-B2
Application number	US-201414455058-A
Country	US
Kind code	B2
Filing date	Aug 8, 2014
Priority date	Apr 25, 2014
Publication date	Aug 9, 2016
Grant date	Aug 9, 2016

Abstract

According to one embodiment, disclosed is a pattern forming method including preparing a second dispersion by adding a second protective group and second solvent to fine particles including a first protective group whose surface polarity is close to that of the substrate, the fine particles containing, at least on the surface thereof, a material selected from Al, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, Y, Zr, Sn, Mo, Ta, W, Au, Ag, Pd, Cu, Pt, and an oxide thereof, modifying the fine particles including the first protective group with the second protective group, adding a viscosity adjustment agent to the dispersion containing the fine particles to prepare a coating solution, and applying the coating solution on the substrate to form a fine particle layer thereon.

First claim

What is claimed is:

1. A manufacturing method of a magnetic recording medium, the method comprising:
preparing a second dispersion by adding a second protective group, which is made of an organic substance with a carboxy group or a thiol group, and second solvent to fine particles including a first protective group, which is made of an organic substance with a carboxy group or a thiol group, the fine particles containing, at least on the surface thereof, a material selected from a group consisting of
aluminum, titan, vanadium, chrome, manganese, iron, cobalt, nickel, zinc, yttrium, zirconium, tin, molybdenum, tantalum, tungsten, gold, silver, palladium, copper, platinum and an oxide thereof,
to modify the fine particles including the first protective group the second protective group in the second dispersion to form the fine particles including the first and second protective groups, the second protective group being dispersed in the second dispersion and packed between the fine particles;
adding a viscosity adjustment agent to the second dispersion to prepare a fine particle coating solution;
applying the fine particle coating solution on a substrate to form a single-layered fine particle layer thereon; and
forming a magnetic recording layer on a periodic pattern formed of the single-layered fine particle layer.

2. The manufacturing method of claim 1 , further comprising, in advance to forming the magnetic recording layer, performing etching of the first and second protective groups using the fine particles as a mask.

3. The manufacturing method of claim 1 , further comprising:
inserting an underlying layer between the substrate and the fine particle layer; and
in advance to forming the magnetic recording layer, transferring the periodic pattern formed of the fine particle layer to the underlying layer using the fine particles as a mask and removing the fine particles.

4. The manufacturing method of claim 1 wherein the second solvent is selected from a group consisting of hexane, 2-butanone, toluene, xylene, cyclohexane, cyclohexanone, PGMEA, diglyme, ethyl lactate, methyl lactate, tetrahydrofuran, and a mixture thereof.

5. The manufacturing method of claim 1 , wherein the fine particles including the first protective group are formed by preparing a first dispersion by dispersing the first protective group and the fine particles in a first solvent, and coupling the fine particles with the first protective group in the first dispersion, and
the second dispersion is prepared by precipitating the first dispersion to remove a supernatant fluid and adding the second solvent in which the second protective group is dispersed to the fine particles including the first protective group.

6. The manufacturing method of claim 1 , wherein a number of reactive functional groups/a surface area of the fine particles is 0.1 to 100/nm 2 .

7. The manufacturing method of claim 5 , wherein the first solvent is selected from a group consisting of hexane, 2-butanone, toluene, xylene, cyclohexane, cyclohexanone, PGMEA, diglyme, ethyl lactate, methyl lactate, tetrahydrofuran, and a mixture thereof.

8. The manufacturing method of claim 1 , wherein the first protective group and the second protective group have a same main chain.

9. The manufacturing method of claim 8 , wherein the first protective group and the second protective group are the same.

10. The manufacturing method of claim 1 , wherein the first and second protective groups contain one of a carboxy group and a thiol group as a reactive functional group.

11. The manufacturing method of claim 10 , wherein, when the fine particles contain, at least on the surface thereof, a material selected form group consisting of aluminum, titan, vanadium, chrome, manganese, iron, cobalt, nickel, zinc, yttrium, zirconium, tin, molybdenum, tantalum, tungsten, and an oxide thereof, the reactive functional group of the first and second protective groups is the carboxy group.

12. The manufacturing method of claim 10 , wherein, when the fine particles contain, at least on the surface thereof, gold, silver, palladium, copper, platinum, and an oxide thereof, the reactive functional group of the first and second protective groups is the thiol group.

13. The manufacturing method of claim 1 , wherein a main chain of the first protective group and the second protective group is at least one selected from a group consisting of saturated hydrocarbon, unsaturated hydrocarbon having a plurality of carbon double binds, polyester, polystyrene, polymethyl methacrylate, polyallyl ether, polyvinyl ether, polyester acrylate, polyester methacrylate and a derivative thereof.

14. The manufacturing method of claim 1 , wherein a molecular weight of the first protective group and the second protective group is from 100 to 50,000.

15. The manufacturing method of claim 1 , wherein the fine particle coating solution is applied on the substrate by a method selected from spin coating, dip coating, and LB.

16. A manufacturing method of a magnetic recording medium, the method comprising:
preparing a second dispersion including a magnetic recording layer by adding a second protective group, which is made of an organic substance with a carboxy group or a thiol group, and second solve to fine particles including a first protective group, which is made of an organic substance with a carboxy group or a thiol group, the fine particles containing, at least on the surface thereof; a material selected from a group consisting of
aluminum, titan, vanadium, chrome, manganese, iron, cobalt, zinc, yttrium, zirconium, tin, molybdenum, tantalum, tungsten, gold, palladium, copper, platinum, and an oxide thereof,
to modify the fine particles including the first protective group with the second protective group in the second dispersion to form the fine particles including the first and second protective groups, the second protective group being dispersed in the second dispersion and packed between the fine particles;
adding a viscosity adjustment agent to the second dispersion to prepare a fine particle coating solution;
applying the fine particle coating solution on a substrate to form a single-layered fine particle layer thereon; and
transferring a periodic pattern formed of the single-layered fine particle layer to the magnetic recording layer.

17. The manufacturing method of claim 16 , when the second solvent is selected from a group consisting of hexane, 2-butanone, toluene, xylene, cyclohexane, cyclohexanone, PGMEA, diglyme, ethyl lactate, methyl lactate, tetrahydrofuran, and a mixture thereof.

18. The manufacturing method of claim 16 , wherein the fine particles including the first protective group are formed by preparing a first dispersion by dispersing the first protective group and the fine particles in a first solvent and coupling the fine particles with the first protective group in the first dispersion, and
the second dispersion is prepared by precipitating the first dispersion to remove a supernatant fluid, and adding the second solvent in which the second protective group is dispersed to the fine particles including the first protective group.

19. The manufacturing method of claim 16 , wherein a number of reactive functional groups/a surface area of the fine particles is 0.1 to 100/nm 2 .

20. The manufacturing method of claim 18 , wherein the first solvent is selected from a group consisting of hexane, 2-butanone, toluene, xylene, cyclohexane, cyclohexanone, PGMEA, diglyme, ethyl lactate, methyl lactate tetrahydrofuran, and

Assignees

• Toshiba Kk

Inventors

• Kimura Kaori
• Fujimoto Akira
• Watanabe Akira

Classifications

• G11B5/855 Primary

  Coating only part of a support with a magnetic layer · CPC title